patch "component: do not dereference opaque pointer in debugfs" added to driver-core-testing

patch "component: do not dereference opaque pointer in debugfs" added to driver-core-testing

[gregkh]

This is a note to let you know that I've just added the patch titled

    component: do not dereference opaque pointer in debugfs

to my driver-core git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git
in the driver-core-testing branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will be merged to the driver-core-next branch sometime soon,
after it passes testing, and the merge window is open.

If you have any questions about this process, please let me know.


From ef9ffc1e5f1ac73ecd2fb3b70db2a3b2472ff2f7 Mon Sep 17 00:00:00 2001
From: Lubomir Rintel <lkundrak@v3.sk>
Date: Mon, 18 Nov 2019 12:54:31 +0100
Subject: component: do not dereference opaque pointer in debugfs

The match data does not have to be a struct device pointer, and indeed
very often is not. Attempt to treat it as such easily results in a
crash.

For the components that are not registered, we don't know which device
is missing. Once it it is there, we can use the struct component to get
the device and whether it's bound or not.

Fixes: 59e73854b5fd ('component: add debugfs support')
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Cc: stable <stable@vger.kernel.org>
Cc: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Link: https://lore.kernel.org/r/20191118115431.63626-1-lkundrak@v3.sk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/base/component.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/base/component.c b/drivers/base/component.c
index 3a09036e772a..c7879f5ae2fb 100644
--- a/drivers/base/component.c
+++ b/drivers/base/component.c
@@ -101,11 +101,11 @@ static int component_devices_show(struct seq_file *s, void *data)
 	seq_printf(s, "%-40s %20s\n", "device name", "status");
 	seq_puts(s, "-------------------------------------------------------------\n");
 	for (i = 0; i < match->num; i++) {
-		struct device *d = (struct device *)match->compare[i].data;
+		struct component *component = match->compare[i].component;
 
-		seq_printf(s, "%-40s %20s\n", dev_name(d),
-			   match->compare[i].component ?
-			   "registered" : "not registered");
+		seq_printf(s, "%-40s %20s\n",
+			   component ? dev_name(component->dev) : "(unknown)",
+			   component ? (component->bound ? "bound" : "not bound") : "not registered");
 	}
 	mutex_unlock(&component_mutex);
 
-- 
2.24.1